below which the radiation cannot eject electrons from the material. [P10.1]
for: a particular material
is: a frequency of electromagnetic radiation below which the radiation cannot eject electrons from the material. [P10.1]
corresponds: to photons whose energy is just large enough to overcome the work function 
of the material and eject photoelectrons of zero kinetic energy. [P10.1]
is given: from Einstein's photoelectric equation, by 
[P10.1]
is: a characteristic of each material and its surface preparation. [P10.1]
Copyright 1997, The Open University